Questions tagged [weather]
Weather means the atmospheric conditions, including wind, temperature and precipitation, in a specific area at a specific time.
297
questions
9
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4answers
440 views
Can the “G” and “VRB” wind conditions be combined in METARs?
I have never seen the "VRB" (for wind direction variations < 60°; e.g. VRB12003KT) and "G" annotation (for gusts > 10KT wind speed difference; e.g. 12003GT30KT) being combined in a METAR.
Until ...
1
vote
1answer
47 views
How would a pilot apply the information found on a 500 Millibar Vorticity chart to a flight?
The U.S. Flight Service website has these weather products listed:
I have circled the 500 Millibar Vorticity Charts. I've been a pilot for 10+ years and have never heard mention of this chart by ...
3
votes
2answers
108 views
Is AMDAR a required system on aircraft?
I was intrigued by the assertion that COVID-19 depressing commercial aviation has lead to lower quality weather forecasting
The aircraft observations are a key piece in the jigsaw of national and ...
5
votes
1answer
107 views
Does a METAR report variable wind direction in a clockwise direction?
Does the convention for reporting variable wind direction always use a clockwise (nautical) sense?
For example, if the wind varies between 340 degrees and 10 degrees, assuming a clockwise sense the ...
2
votes
1answer
68 views
Is an area of localized reduced visibility considered to be a cloud?
If there an area containing visible moisture in an otherwise clear sky and that area of visible moisture is transparent is it considered a "thin cloud" or simply a "localized area of reduced ...
2
votes
1answer
92 views
What is an approved weather source for flying an instrument approach into an airport with no working ATIS?
What can you use as viable weather information landing at an airport with ATIS inoperative due to the tower being closed after hours? Let's assume the approach secondary weather source is also ...
12
votes
2answers
2k views
Who makes the call to start in terrible weather conditions?
I once headed to the airport during a huge thunderstorm with winds above 55 knots and massive rain and some small hail. At the airport, I saw that most flights were delayed or even canceled. To my ...
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vote
2answers
298 views
Are helicopters impacted by fog more than airplanes?
With the crash of Kobe Bryant's helicopter, it seems a lot of focus has been placed on the helicopter flying low in fog (under "special VFR"). However, I've seen several suggestions that the ...
4
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0answers
174 views
How far can the sound of a sonic boom travel? [closed]
Are there conditions or distances from the plane to cloud to the observer in which a sonic boom from a plane is muted?
0
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2answers
96 views
Why and how do atmospheric properties sometimes vary from the ISA? [closed]
I'm curious as to why sometimes atmospheric properties don't match the ISA's. One reason I am considering is due to calibration discrepancies. By atmospheric properties I mean temperature, Density, ...
14
votes
5answers
7k views
Why did my LGA-ORD flight make an S-shaped turn round the time it was passing a storm?
On a recent United UA1709 flight into Chicago (hit by a heavy storm at the time), I felt a noticeable descent, combined with two wide banks around 1 hour before landing. Looking at the flight path, I ...
10
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1answer
1k views
How do pilots avoid thunderstorms at night over the pacific en route to Australia where there is no radar? And what if a large front develops?
While there is some limited radar on board for pilots, we hear that there is no radar over the ocean which is why flight locations are estimated. As the distance between the United States and ...
4
votes
1answer
197 views
What to do if trapped on top VFR?
In the event that, despite his best efforts, a VFR-only pilot has gotten trapped on top of a solid cloud layer, what is(are) the safest course(s) of action?
For example, consider a long cross-country ...
2
votes
1answer
106 views
How to avoid getting trapped on top VFR?
This question addresses whether it is legal to fly VFR over-the-top.
One of the comments mentioned the difference between safety and legality, i.e. doing so may not be safe even if it is legal (in ...
2
votes
1answer
3k views
What fomula use for calculating pressure altitude?
I'm having some trouble making my calculations of pressure altitude match those in apps and text books.
I'm using the formula from Wikipedia:
(29.92 - altimeter setting) * 1000 + airport elevation ...
0
votes
0answers
34 views
Where can I find NWS Surface Analysis charts?
It seems that a lot of documentation for getting the 'big picture' for aviation weather refers to 'Surface Analysis Charts'. For example AC 00-45H 4.1 talks about NWS Surface Analysis charts. However ...
2
votes
1answer
323 views
What is the difference between ACARS and ADS-B?
What is the difference between ACARS and ADS-B?
For weather information in-flight or pre-flight which one is used?
7
votes
1answer
1k views
Does the coriolis force have an effect on the direction in which an aircraft travels?
Suppose an aircraft is flying from Kenya (which lies on the equator) to UK (which lies in the northern hemisphere). Does the Coriolis force veer the aircraft to the right? Do pilots have to correct ...
1
vote
1answer
298 views
Can you continue an ILS approach when weather falls below minimum?
If, after passing the final approach fix, weather deteriorates so that the reported values are now below required minima, is it allowed to continue the approach?
1
vote
1answer
120 views
What is the reasoning behind this question about the correct altitude to avoid clear icing?
This question has been killing me for a while and it's an original PPL question:
You are approaching to an airmass with a temperature of 6 C at
10000ft. Which altitude should you be in order to avoid ...
1
vote
1answer
121 views
Why jet stream is stronger in winter?
I notice in a website taling about jetstream
https://www.weather.gov/jetstream/jet
It says:
The winds blow from west to east in jet streams but the flow often shifts
to the north and south. ...
0
votes
4answers
110 views
Can airflow reverse over the flight surfaces of a uav in high wind conditions
Can airflow reverse over the wing of a uav in high tail winds and low forward airspeed i.e 25knt fwd airspeed in a 35 knt tailwind? What would be the overall effect on the elevator and rudder? I ...
3
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2answers
488 views
Approach when weather condition is below minimum
If airport weather condition is below minimum, but pilot report that flight weather condition is above minimum, Does controller can issue approach clearance to pilot?
If weather condition get worse ...
6
votes
3answers
161 views
NEXRAD—why is it 2D?
If you paid attention to NEXRAD training, you know that the colors of pixels show the maximum activity at any altitude in that air column. (It’s a “composite” view.)
NEXRAD itself samples in three ...
22
votes
3answers
6k views
How did pilots avoid thunderstorms and related weather before “reliable” airborne weather radar was introduced on airliners?
How did airline and or mail pilots avoid hazardous weather especially at night before airborne weather radar systems were in use?
3
votes
1answer
205 views
Does an uncovered naval aircraft suffer any weathering affects?
This question is for WW2-era naval aircraft.
I noticed that some cruisers and battleships carried a couple seaplanes, launched by catapult and recovered with cranes.
Obviously these are unprotected ...
3
votes
2answers
2k views
What does NSC mean in a METAR?
Here's a METAR:
SCEL 090000Z 15005KT 5000 HZ NSC 10/08 Q1020 NOSIG
What does NSC mean?
18
votes
3answers
2k views
When do flights get cancelled due to fog?
When flights get cancelled due to fog, what triggers the cancellation? Fog is too thick, too wide-spread, blocks the view of tall buildings or other landmarks? Or is the problem the type of air ...
5
votes
1answer
121 views
What kind of input is used by NASA's TASAR?
I've found the Aviation SE to be a really interesting read so far, I'm excited to be here! I'm fairly new, but I'm also old!
What are the inputs for TASAR to crunch flight path optimization? Is it ...
0
votes
1answer
72 views
What the weather condition can affect for flight? [closed]
What is the most disturbing weather conditions for flight?
On another word: what more dangerous for takeoff/landing: wind, precipitation or something else?
0
votes
3answers
147 views
What does the future of the weather radars look like?
Planes had weather radars for a long time (Dassault Falcon and Learjet35A) which was useful since you either had to ask ATC, listen the ATIS frequency or ask the flight advisory before flight planning ...
6
votes
4answers
998 views
What is an “all-weather” aircraft?
I've read a few times that such-and-such a plane is an "all-weather" aircraft, for example:
The McDonnell Douglas F/A-18 Hornet is a twin-engine, supersonic, all-weather, carrier-capable, multirole ...
2
votes
1answer
752 views
What are the duration of TAFs?
TAFs (terminal aerodrome forecast) have different durations. Some forecasts 30 hours into the future while others forecasts only 24 hours.
But what is the shortest and longest TAFs? and how often are ...
0
votes
2answers
496 views
What is the relation between clouds and radar effectiveness?
Recently, India's prime minister Narendra Modi commented on how cloudy weather can help a fighter jet escape from radar. Is there any technical reasoning to back these comments?
Here is the quote ...
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1answer
583 views
For an airport to be designated as an IFR alternate, does it have to have a TAF?
For an airport to be designated as an IFR alternate, does it have to have a terminal aerodrome forecast at the alternate airport to confirm that the forecast 600-2 and 800-2 will be in place at the ...
4
votes
1answer
249 views
Why is a small amount of smooth ice over the top of the wing more dangerous than an accumulation on the leading edge?
According to a Gleim study guide,
"Generally speaking, smooth ice on top of the wing is more dangerous than heavy accumulated icing on the leading edge."
Is this true? If this is true, why?
9
votes
3answers
805 views
Are there more accidents in winter months, and if so, why?
I was watching The Flight Channel videos and have noticed that the accidents seem to happen more often in winter months (for the Northern Hemisphere). Are there some statistics to back this claim?
It ...
2
votes
1answer
778 views
What is the meaning of R88/70D in this METAR from Ashgabat International airport?
The following METAR is from Ashgabat airport (UTAA)
UTAA 071300Z 13006KT 9999 FEW050CB BKN050 BKN100 15/06 Q1013 R88/70D
NOSIG
What does R88/70D mean, I couldn't find any references?
3
votes
1answer
166 views
Is navigation around thunderheads done at the pilot's discretion?
It's my understanding that if a pilot is flying over an ocean or otherwise uncontrolled airspace and they encounter a cumulonimbus, they navigate around it at their discretion.
How does this happen ...
3
votes
3answers
2k views
What is the purpose of including sea level pressure and temperature in a METAR?
In a METAR such as this one:
KGOK 161553Z AUTO 18011KT 4SM BR OVC007 07/05 A3011 RMK AO2 SLP201
T00670050
Translated to:
Jan 16, 1553Z, Automated. Mist, Wind from 180° at 11 knots, 4 statute
...
1
vote
3answers
133 views
How is the effect of wind on arrival time handled?
If a commercial plane encounters strong tailwinds, would the pilots set the autopilot for a fixed arrival time (if that is possible), or would it be ok to arrive way ahead of schedule?
I imagine ...
3
votes
1answer
137 views
When is a high pressure system associated with IFR/MVFR conditions?
So I've read that typically high pressure systems bring good weather and clear skies. However, for the current high pressure system we're experiencing in central USA, we're having quite a bit of IFR/...
1
vote
1answer
59 views
Can a SIGMET last less than initially forecasted?
Lets say I have a SIGMET that says VALID 310800/311200.
Is it possible that by 1100 the SIGMET would not be active anymore or it will always be valid until the published end time?
-1
votes
3answers
466 views
Did AF447 cross dangerous weather?
question
Did the Air France 447 pilots endanger the passengers by not diverting around but flying straight through the weather system encountered and pictured below ? Or was this a defendable, ...
2
votes
1answer
456 views
When do pilots facing bad weather turn back (U-turn)?
Passenger aircraft are not supposed to cross red areas on the weather radar. But what if the weather system is too large to circumnavigate and red areas inside the system are too large/prevalent to ...
8
votes
4answers
228 views
Are winds that are not from the prevailing wind direction more often gusty, and why?
It seems to me that, looking at the ground weather forecasts (as opposed to, say, low level forecasts), it's far more common for the wind to be predicted to be significantly gusty when it is blowing ...
3
votes
3answers
792 views
How do pilots decide whether to circumnavigate bad weather?
How does an airline pilot decide in the air whether to circumnavigate or fly through bad weather visibly looming ahead and/or displayed on the weather radar ?
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0answers
65 views
What is the specific FAA regulation with regards to a pilot dropping jumpers into a solid cloud base? [duplicate]
What is the FAA regulation with regards to a pilot dropping jumpers into a solid cloud base? I saw some parachute jumpers come through a solid cloud layer with a base at around 1300 AGL. They landed ...
1
vote
1answer
317 views
Do any civilian aircraft use AESA or PESA for weather radar?
Are there any weather radars in civilian aircraft that uses active or passive array techniques? I know that the most of the radar used in the civilian aircraft use doppler effect and latest military ...
3
votes
1answer
327 views
What if the tower Is obstructed by clouds?
I know towers use radar to watch aircraft, obviously. But what about ground controllers? What if their view is obstructed by a low cloud level/fog?
Is there such a thing as ground-based traffic ...
